These look like 5 min charts?
My own trading strategy is very similar to this and always has been. But I do not trade such short term charts. My own stalking ground is on the 4h/1h combo. A 200 EMA might sound like a long time but on a 5min chart that is still an intraday time period and therefore more reflective of daily fluctuations rather than any underlying trend.
I say this because waiting for short term EMA’s to actually cross over the 200 EMA on a 5min chart is likely to miss the early part of a move and, even worse, get you in just at the point where the intraday price action starts a swing in the other direction! 
Personally, I only use the 200 EMA has a guide to overall direction/trend strength. It is worth remembering that the benefit of using these three EMAs is in comparing the recent direction relative to the more distant movement. I.e. Price action is making a significant change in direction (but we do not know for how long or how far!).
Therefore, I don’t think waiting for an actual crossover of two short term EMA’s over the 200 EMA is necessary or even recommended. However, when the shorter EMA’s turn in towards the 200EMA it is a sign of a pullback or consolidation. Whether it is worth trading this or not is a subjective decision. I often do take such a trade if there is plenty of room towards the 200EMA, looking for a return to, or near to, its value.
On the other side, when price is above all three EMA’s and all three line up then it is a good sign of a trend and maybe a trailing stop is better than a nearby TL. But, again, I would only do that on longer timeframes and not the 5min, where moves, by definition, tend to be shorter.
One point worth noting when using the 50 and 200 EMA’s. The 200EMA on a 15min chart is a proxy for the 50EMA on the 1h chart, and the 200EMA on the 1h chart is a proxy for the 50 EMA on a 4h chart. So when looking at the 200EMA on the lower TFs, you are actually simultaneously looking at the 50EMA on the higher TF (where the multiple is x4). This can be a useful way of handling multiple timeframes.
As a word of warning, though. EMA values are simply the result of a mathematical formula. If prices always moved with the same speed and volatility, as in sine waves, then this would be fine. But prices jump about sometimes smoothly and gently, sometimes roughly and erratically. Moving averages cannot handle that very well and so crossovers are generally a poor basis for trade entry decisions - and even worse for trade exits (where prices move faster at trade-ends compared with trend-starts).
As a result, in general, I would say that EMA’s are far better as part of a discretionary trading system rather than as the basis for a strictly rules-based system. One can curve-fit EMA’s to any sample of price action - but that does not mean it will successfully repeat itself in future price movements…
Don’t know if that is any help but maybe something to think about!
